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Finding the Fourth Proportional to 619.20, 928.80 and 388.32

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Solution

The fourth proportional to 619.20, 928.80 and 388.32 is: 582.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.20 : 928.80 = 388.32 : x
  2. Step 2: Convert to fraction form
    619.20/928.80 = 388.32/x
  3. Step 3: Cross multiply
    619.20x = 928.80 × 388.32
  4. Step 4: Simplify right side
    619.20x = 360,671.62
  5. Step 5: Solve for x
    x = 360,671.62/619.20
  6. Step 6: Final answer
    x = 582.48

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.